To investigate the effects of lipopolysaccharide (LPS) and human recombinant interleukin-2 (hrIL-2) on the synthesis of sulfated macromolecules in cultured rat GECs.With 3H-thymidine (3H-TdR) and 35S-Na2SO4 dual isotope labelling technique, the proliferation and synthesis of sulfated macromolecules in cultured rat GECs were estimated according to the 3H-TdR uptake and 35SO4(2-)-contents in cell layers respectively.Both LPS (6.25-50.0 micrograms/L) and hrIL-2 (2.5-10.0 kU/L) decreased the uptake of 3H-TdR by GECs (P < 0.05). As for incorporation of 35SO4(2-) into cell layers, the results that both means and adjusted means in hrIL-2 groups were lower than those in controls (P < 0.05) implied that hrIL-2 could inhibit the synthesis of basement membrane HSPG while LPS hindered incorporation through its inhibitory effect on cell proliferation.We may infer from these results that LPS-like proinflammatory mediators could increase the subpopulation of large pores in capillary wall through the reduction of cell-associated HSPG, and IL-2-like cytokines could contribute to the development of proteinuria through its inhibitory effect on the production of basement membrane HSPG in immune-mediated glomerular disorders.